---
title: "AT Commands"
url: "https://maker.wiznet.io/forum/11167"
markdown_url: "https://maker.wiznet.io/forum/11167/md"
type: "Forum topic"
category: "Wireless"
author: "Damowerko"
created: "2015-07-09T15:21:01+09:00"
last_activity: "2017-05-04T08:39:01+09:00"
language: "en"
views: 1225
replies: 4
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# AT Commands

## Question

Asked by Damowerko on 2015-07-09 in Wireless.

Hello,

I am trying to use the Serial Monitor of arduino to send AT commands to test out the shield, because the example programs did not work. However, once I send an ‘AT’ through the serial monitor there is no reply.

I am using Arduino UNOr3 with ArduIDE 1.5.5.

I stacked the shield on top of the Arduino.

## Replies

### Reply 1 by wizdaniel, 2015-07-10

Hi damowerko

Can you tell me what kind of WizFi210 which you own?

A WizFi Shield & a WizFi210 library(for arduino) are operated on SPI interface.
but, WizFi210-EVB was working at the UART interface.

Is that right the library you used?
[github.com/Wiznet/WizFiShield](https://github.com/Wiznet/WizFiShield)

### Reply 2 by Damowerko, 2015-07-10

I am using the 210 shield. Yes, that is the library I used - it had compilation errors on ArduinoIDE 1.6.5 so I had to downgrade to 1.5.5.

When I launch the example sketches and open serial monitor it does not go beyond checking weather the shield is responding:

Serial Init
Send Sync data
Rcving Sync Timeout!!

This is the beggining of the code where it stops:

```
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <SPI.h>
#include <WizFi2x0.h>
#include <WizFiClient.h>
#include <TimerOne.h>

#define SSID    ""        // SSID of your AP
#define Key     ""  // Key or Passphrase
// Wi-Fi security option (NO_SECURITY, WEP_SECURITY, WPA_SECURITY, WPA2PSK_SECURITY)
//#define Security        WPA_SECURITY

unsigned char  SIP[4] 	= {192, 168, 1, 7}; // Server IP address to connnect
unsigned int ServerPort = 5000;  // Server port number

WizFi2x0Class myWizFi;
WizFiClient myClient;

boolean Wifi_setup = false;

// 1msec Timer
void Timer1_ISR()
{
  uint8_t i;
  
  myWizFi.ReplyCheckTimer.CheckIsTimeout();
}
void setup() {
  byte retval;
  
  Serial.begin(9600);
  Serial.println("\r\nSerial Init");
  
  // initalize WizFi2x0 module:
  myWizFi.begin();
  myClient =  WizFiClient(SIP, ServerPort);
   
  // Timer1 Initialize
  Timer1.initialize(1000); // 1msec
  Timer1.attachInterrupt(Timer1_ISR);
 
  myWizFi.SendSync();
  myWizFi.ReplyCheckTimer.TimerStart(3000);
  Serial.println("Send Sync data");
  
  while(1)
  {
    if(myWizFi.CheckSyncReply())
    {
      myWizFi.ReplyCheckTimer.TimerStop();
      Serial.println("Rcvd Sync data");
      break;
    }
    if(myWizFi.ReplyCheckTimer.GetIsTimeout())
    {
      Serial.println("Rcving Sync Timeout!!");
      // Nothing to do forever;
      for(;;)
      ;
    }
  }
```

### Reply 3 by wizdaniel, 2016-03-03

Hi

WizFi210 shield can support 1.0.x version of arduino IDE…
please try it 1.0.x IDE

### Reply 4 by KellyTurci, 2016-09-04

Hi…i am a new user here. Can you tell me what kind of WizFi210 which you own?A WizFi Shield & a WizFi210 library(for arduino) are operated on SPI interface.But, WizFi210-EVB was working at the UART interface.

---

Source: https://maker.wiznet.io/forum/11167